Abstract
As already shown, some inducers of the differentiation of promyelocytic cells along the granulocytic pathway, such as dimethylsulphoxide (DMSO) or all-trans retinoic acid, can enhance propagation of granulocytic ehrlichiae in HL-60 cell cultures. This study was conducted to prove whether sodium valproate, a salt of di-n-propylacetic acid (VPA) known to trigger cellular differentiation in several solid and hematopoietic malignancies is similarly efficient in ehrlichial cultures. Two cell lines derived from HL-60. that is, low-passage undifferentiated HL-60 (HL-60F) and high-passage HL-60 spontaneously differentiated towards monocytic phenotype (HL-60J) were grown in RPMI 1640 medium supplemented with 10% FBS. The respective HL-60F and HL-60J IC50-values for NaVPA were estimated to he 0.8 and 2.2 mM under these culture conditions: to stimulate the differentiation, the respective doses of 0.3 and 1.2mM were then applied. When the NaVPA-treated cells of both lines were challenged with an ehrlichial laboratory strain (HGE). maintained in splenectomized NMRI mice, the respective l–2 and ≤0.1% primary infection rates in HL-60F and HL-60J cultures were observed 3 days post-inoculation. In comparison, only rare (≤0.1%) infected HL-60F and no infected HL-60J cells were recorded under the same experimental conditions in untreated control cultures. HGE continuously propagated in NaVPA-supplemented HL-60F cultures remained infectious to mice at least up to the 95th passage (12 months). NaVPA can thus facilitated continuous propagation of granulocytic ehrlichiae in cell cultures without a substantial loss of infectiveness.
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© 2003 Springer Science+Business Media Dordrecht
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Zeman, P., Cinatl, J., Kabickova, H. (2003). Sodium valproate facilitates the propagation of granulocytic ehrlichiae (Anaplasma phagocytophilum) in HL-60 cells. In: Jongejan, F., Kaufman, W.R. (eds) Ticks and Tick-Borne Pathogens. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-3526-1_19
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DOI: https://doi.org/10.1007/978-94-017-3526-1_19
Publisher Name: Springer, Dordrecht
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